There is a lot of information on Wildlife Tracking on the
Homing In web page (www.homingin.com
). This comes from a
number of requests from researchers asking for hams to
help track migrating birds, etc. There are links there
to other information as well. Some of the birds tracked
were in the 150 or 170 MHz range.
Generally a transmitter needs to operate for several
months to be useful, and needs to be small enough not to
inconvenience the bird (or other animal) carrying it.
You won't find much continuous telemetry being sent unless
it is a pretty good sized animal that doesn't wander far
so the batteries can be changed. (A bear, for example.)
Otherwise you will get very short pips out of the
transmitter at very low power, often unmodulated.
There are other telemetry sources that are more likely,
such as water/snowpack monitoring. Perhaps you can
make a small DF loop and track down the signal?